BIGtrack 2.0 Trackball - for Users who Lack Fine Motor Skills to Use a Mouse. A Big 3&rdquo; Trackball With 2 Blue (Left and Right Mouse) Buttons -#12000006 BIGtrack 2.0 is USB mouse that includes a large 3-in / 7.62-cm trackball and over-sized left and right click buttons. The large ball requires less fine motor control than a standard trackball and it is ruggedly built. It has a left and a right mouse and special Drag Lock. Features a 3-inch yellow ball and has two blue buttons (for left and right mouse clicks) located behind the trackball to avoid unwanted clicks and special Drag Lock feature for ease of access. BIGtrack 2.0 is compatible with most laptop, desktop, and tablet computers that can use a standard mouse. One USB Type A receptacle is required. The BIGtrack Trackball is an easy and effective way to move the mouse cursor across the screen. he giant yellow ball makes it easy to get the cursor precisely where you want it. BIGtrack Features Large 3-inch trackball Oversized left and right mouse click buttons Drag-lock feature Available in a switch adapted version USB or PS2 connection to Windows or Mac computers PC and Mac compatible